MAY 20 - Apples and fish sound an unlikely food combination, even for a pregnant woman, but new evidence suggests they can protect unborn children against allergic diseases.

Researchers found that children whose mothers enjoyed munching apples while pregnant were less likely to have suffered from wheeze or been diagnosed with asthma by the age of five.

Similarly, the sons and daughters of mothers who ate fish once or more a week during pregnancy appeared to be protected against the skin allergy eczema.

Scientists believe the effects may be due to powerful antioxidants in apples called flavonoids, and omega-3 fatty acids in fish.

A range of other foods studied, including vegetables, fruit juice, citrus and kiwi fruit, whole grains, dairy fat and margarine, did not produce the same protective effects.

The investigation was conducted at the University of Aberdeen in Scotland. Researchers studied 1,212 children born to women who had filled out food questionnaires during their pregnancy.

When the children reached the age of five, the team questioned the mothers about their offspring's respiratory symptoms, allergies, and diet.

The children were also given lung function and allergy tests.

Children whose mothers ate the most apples were less likely to have experienced wheeze or asthma than those whose mothers had the lowest apple consumption.

Mothers who ate fish once or more a week while pregnant had children who were less likely to have had eczema than children of mothers who never ate fish.

Previous studies involving the same group showed that taking vitamins E and D and zinc during pregnancy helped reduce a child's risk of wheeze and asthma.

Researcher Saskia Willers, from Utrecht University in the Netherlands, said a mother's pregnancy diet may have more influence on a child's respiratory health than the child's own food consumption - at least until the age of five.

She said: "Other studies have looked at individual nutrients' effect on asthma in pregnancy, but our study looked at specific foods during pregnancy and the subsequent development of childhood asthma and allergies, which is quite new.

"Foods contain mixtures of nutrients that may contribute more than the sum of their parts."

The findings were presented today at the American Thoracic Society's annual meeting in San Francisco.